Nathan F
sage
Reged: 10/10/08
Posts: 223
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In your opinion, what top five mirror makers consistently make the best primary mirrors, regardless of cost? Which of the five do you rank as the very best?
I'm most interested in hearing from those with experience testing multiple mirrors in a systematic, scientific manner, rather than anecdotal evidence about singular mirrors from personal scopes, brief views had at star parties, or popular opinion.
Looking forward to seeing whatever one has to say!
-------------------- 12 inch f/5 Deep Space Observer Dob
31mm Nagler, 13mm Ethos, 1.6x Antares 2 inch Barlow
Celestron SkyMaster 15x70 Binoculars
Homemade Maple Parallelogram Binocular Mount
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llanitedave
Humble Megalomaniac
   
Reged: 09/26/05
Posts: 12944
Loc: Amargosa Valley, NV, USA
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It will be interesting to see how many folks here have had enough different mirrors to pick out a top five batch.
-------------------- "Since the process of science generates more mysteries than it solves, I predict that we'll never learn everything: and we'll continue to generate new ignorance at the speed of knowledge."
"S.O.E." (Sauron's Other Eye), with 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Under Construction: The "Eye of Sauron" Observatory!
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Mike I. Jones
Carpal Tunnel
   
Reged: 07/02/06
Posts: 1572
Loc: Fort Worth TX
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Carl Zambuto figured the two 18" f/8 fused silica primaries for the new McDonald Observatory Wren-Marcario Accessible Telescope (WMAT). I tested one in my shop and found the figure to be extremely smooth, with an essentially perfect diffraction ring, and the Foucault and wire test numbers coming in at the 1/25 wave RMS range. I didn't test the other primary, but the data sheet indicated a similar degree of correction. A lot of us have made a few personal mirrors equal to this precision, but not consistently to this precision by the thousands for commercial sales as Carl has achieved. I would put Carl up there among the best in the world. John Hudek at Galaxy Optics and Paul Jones are also up there with Carl.
Mike
Mike
-------------------- 56 mirrors, lenses, 16" f/6 Newt, 6" f/10 refractor, TOA-130S, Tinsley 5" f/15 Mak, 6" f/4 RFT, Coronado PST. Still to build: 24" f/10 Modified Dall-Kirkham, 10" f/26 Mak, 8" f/12 apo, spectrohelioscope, Herrig, Schupmann, and others.
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dave b
Post Laureate
Reged: 05/10/05
Posts: 3548
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our club has tested hundreds of mirrors, without a doubt, zambuto is the best example in every size.
other mirror makers sometimes make good mirrors, but other times release junk you cant believe even an amateur would call finished - let alone claim to be strehl .995
because of this, i cant even give a top 5. once you let a bad optic "slip" out with sham paperwork, you are forever tainted.
every mirror from kennedy i have seen has been great, but we have not had enough samples yet to put him up there with zambuto. ask again in 5 years maybe.
-------------------- dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
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polaraligned
sage
Reged: 12/26/08
Posts: 233
Loc: P. R. of New Jersey
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If you want to go big (22"+) and sub f/4, I know of no body capable besides Mike Lockwood and Steve Kennedy. Kennedy having the edge as he has produced probably more sub f/4 large mirrors than anyone else. Unfortunately, he does not do custom orders and do substrates other than monolithic pyrex. Hopefully that will change soon.
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davidpitre
Carpal Tunnel
   
Reged: 05/10/05
Posts: 1826
Loc: Central Texas
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Quote:
Carl Zambuto figured the two 18" f/8 fused silica primaries for the new McDonald Observatory Wren-Marcario Accessible Telescope (WMAT).
Mike
Mike. What is that? I haven't heard of it.
-------------------- David
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Nathan F
sage
Reged: 10/10/08
Posts: 223
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I was expecting a heated debate! Where is the drama? The intrigue? 5 posts is it?
-------------------- 12 inch f/5 Deep Space Observer Dob
31mm Nagler, 13mm Ethos, 1.6x Antares 2 inch Barlow
Celestron SkyMaster 15x70 Binoculars
Homemade Maple Parallelogram Binocular Mount
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Chris Curran
scholastic sledgehammer
   
Reged: 06/14/05
Posts: 827
Loc: Brandon, FL
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I'm most interested in hearing from those with experience testing multiple mirrors in a systematic, scientific manner,
You're not going to get that here. If you really want to trust this info, save up some cash, buy a bunch of mirrors and submit them to your favorite optical lab for testing. Saving that, you're going to have to put up with anecdotal evidence about singular mirrors from personal scopes, brief views had at star parties, or popular opinion. 
My vote is Royce. Royce Conical mirrors are equal in performance to anything else you can buy, and they have a unique and brilliant mounting method to boot.
-------------------- cheers & beers,
Chris
Homepage | Over 40?
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polaraligned
sage
Reged: 12/26/08
Posts: 233
Loc: P. R. of New Jersey
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Quote:
I was expecting a heated debate! Where is the drama?
That is exactly why nobody is posting.
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Mark Harry
Post Laureate
   
Reged: 09/05/05
Posts: 3128
Loc: Northeast
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It's expected to remain civilised as per the intent of the TOSS. I've tested a carload of mirrors 14" and under. In retrospect, my testing regimen is very reliable, as long as I'm the one using the rig. I'm the only set of eyeballs I personally trust. I spot things others miss completely; even on interferometric reports. Short of buying a mess of mirrors as Chris mentions, maybe you should choose someone who can test reliably; and have them take a peek at what you want to buy??????? I've also tested quite a few mirrors, free of charge. Just include return shipping. If interested, PM me. Mark
-------------------- So many projects, so little time!
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Sean Cunneen
Let Me Think
   
Reged: 08/01/07
Posts: 1229
Loc: Blue Island Illinois
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Try a thread like this in the refractor forum if your after excitment. The names brought up here fit what I would think should be included with the exception of Discovery which from my personal experience makes a very good mirror. Of course there is only one Discovery mirror, it just gets passed around a lot, hence all the long waits.
-------------------- Sean Cunneen
Blue Island, IL
12.5" Ultralight Strut Dob
127mm f/9 refractor
35Pan, 10XW, 5XO
Member of the Calumet Astronomical Society
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Chris Curran
scholastic sledgehammer
   
Reged: 06/14/05
Posts: 827
Loc: Brandon, FL
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-------------------- cheers & beers,
Chris
Homepage | Over 40?
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davidpitre
Carpal Tunnel
   
Reged: 05/10/05
Posts: 1826
Loc: Central Texas
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I would put John Hall of Pegasus up there with the best. I've used quite a few of his mirrors in the field and have never seen even one that was less than excellent+ . I'd say the same of Carl Zambuto. I can't think of anyone else I could say that of, though that is not to put any other makers down. ' just my personal experiences.
-------------------- David
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bbasiaga
professor emeritus
   
Reged: 05/10/06
Posts: 724
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I have a nice discovery mirror, though I have not had it tested. I will say I got it ahead of schedule, no problems at all.
I went with Swayze for my current project. I've looked through several scopes made with his mirrors here, and they are awesome.
-Brian
-------------------- Vixen 80EDSF
Stellarvue 102ED2
Orion Atlas 11 EQ-G
15" Astrosystems Telekit w/ Discovery Optics
Lust for something Larger
Lust for something Larger than that
Past Lovelies:
Oberwerk 20x100 binocs
Meade AR5
Meade LX10 8" SCT
All sold to a good home
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roscoe
super member
Reged: 02/04/09
Posts: 192
Loc: Northwestern Mass
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Another vote for Steve Swayze, or at least a certification that he is an honest mirror man...........I bought a miror used, had the seller ship it direct to him for evaluation. and he called to tell me that in current condition, it was best as a doorstop. He could easily have said "good enough", sent it out to be recoated, and sent me a bill. I have observed with Royce mirrors, they sure seemed to do their job well!!!!
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Gert
member
Reged: 04/15/08
Posts: 33
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Hi All,
Please consider Zeiss and Perkin Elmer as well. For a Price they will do what ever you specify.
Clear Skies,
Gert
Edited by Gert (06/25/09 09:56 PM)
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Jeff Morgan
Carpal Tunnel
Reged: 09/28/03
Posts: 1987
Loc: Prescott, AZ
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Good luck. Most people buy from a single supplier until that supplier lets them down. For example, I am on my fourth Royce mirror, and #5 will also be from Royce. He has not given me even the slightest room for doubt, misgiving, or buyers remorse. Add to that the conical is a great concept.
Bottom line, very few people will have a large number of samples from a large number of suppliers. Since people tend not to "churn", that speaks well for all of the known premium suppliers.
-------------------- Jeff Morgan
Prescott, AZ
Wile E. Coyote School of Telescope Making
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Mike I. Jones
Carpal Tunnel
   
Reged: 07/02/06
Posts: 1572
Loc: Fort Worth TX
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I don't want to hijack this thread but I'll mention this briefly.
Installation of the WMAT optics is underway this week and next. First light was this evening, and the images were spectacular through both the north and south mirrors Carl figured for us. Many more pictures to come once the installation is complete.
WMAT is presently the only two-mirror Pfund telescope in the world. The central 24" diameter perforated flat is mounted on an alt-azimuth tracking mount, and feeds either the north or south 18" f/8 paraboloid selected, thus giving full sky coverage.
The WMAT website has been updated. Check it out at
http://idisk.mac.com/rwren/Public/wmwat2/index.htm
Bill should be putting up the newest installation pictures over the next few days there.
I did the optical design for WMAT way back in 2005-6, so it's really exciting to see it finally come together in real hardware. The huge custom 2" binoviewers are going to really knock everyone's socks off.
Mike
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peleuba
sage
Reged: 12/01/04
Posts: 292
Loc: Southern PA
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Quote:
Good luck. Most people buy from a single supplier until that supplier lets them down. For example, I am on my fourth Royce mirror, and #5 will also be from Royce. He has not given me even the slightest room for doubt, misgiving, or buyers remorse. Add to that the conical is a great concept.
This is exactly the reason I purchase only Zambuto mirrors; I've owned six of his mirrors of various apertures. I've gotten to know Carl over the years and he has never let me down. I have not purchased other's glass, because I've never had a reason to look elsewhere.
Consistent excellence is a wonderful thing and a great customer retention tool.
-------------------- Paul Leuba
TEC160FL #025
StarMaster 14.5 goto/track
Portaball-8
Canon 10X30 IS Binocs
Sets of Nagler T4's, T5's, T6's, TAK LE's, TV Plossls
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NHRob
Post Laureate
   
Reged: 08/27/04
Posts: 3159
Loc: New Hampshire
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Zambuto Royce Swayze Spooner John Hall
Do I have to stop at 5?
Rob
-------------------- Rob
**********************
Canon 12x36 IS binos
TEC-140: #433 on CGEM
Faworski orthos (7,10,16.7mm)
stuff ...
no free time ... lots of clouds !
" Life is what happens to you while you're busy making other plans" !!
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